517 bandgap-ptat

517 : bandgap-ptat

Design render

How it works

A Brokaw bandgap reference using SKY130 PNP BJTs. A PTAT current generator feeds a summing amplifier with OTA feedback to produce a stable ~1.2V reference voltage.

How to test

Apply 1.8V VDD and measure ua[5] (Vref). Expected output is ~1.2-1.3V. Sweep temperature from -40°C to 125°C to characterize stability.

External hardware

None.

IO

#InputOutputBidirectional
0
1
2
3
4
5
6
7

Analog pins

uaPCB PinInternal indexDescription
0B511VRef

Chip location

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